Nut-tapping machine.



W. D RIGNEY.

NUT TAPPING MACHINE.

APPLICATION mwocnzs. 1914.

Patented July 20', 1915.

e sw ms-sheer l.

WITNESSES w. n. RIGNEY.

NUT TAPPING MACHINE.

APPLICATION FILED 0cT.'23,1914.

Patented. July 20, 1915.

' 6 SHEETS-SHEET 2.

w/ TNESSES Arfa/qvvtys.

s SHEETS-SHEET 3..

"Lu v Patented July 20, 1915.

w. 0. RIGNEY.

- NUT TAPPING MACHINE.

APPLICATlON FILED OCT. 23, I914.

w/ms ssis W. D. RIGNEY. NUT TAPPING MACHINE.

APPLICATION FILED OCT. 23, I914.

Patented July 20, 1915.

6 SHEETS-SHEET 4..

ATTORNEYS w. 0. RIGNEY.

NUT TAPPING MACHINE.

APPLICATIONFILED OCT. 23, 1914.

1,147,267. Patented 20 15-.

6 SH SHE w/r/visszs 7 \4 W. D. RIGNEY.

NUT TAPPING MACHINE.

APPLICATION FILED OCT. 23. 1914.

' Patented July 20, 1915.

6 SHEETSQSHEET 6.

W/TNESSES 'I Wit/V70? 5% I HEM: f

WILLIAM I). RIGNEY, 0E PoR'r CHESTER, NEW YORK, ASSIGNOR T0 RUSSELL,

BURDSALLdz wann BOLT AND NUT COMPANY, 0E PORT CHESTER, NEW YORK, A CORPORATIQN OF NEW YORK.

NUT-TAIPIING MACHINE.

Specification of Letters Patent.

Patented July 20, 1915.

Application filed October 23, 1914. Serial No. 868,240.

To all whom it may concern:

Beit known that I, WVILLIAM D. RIGNEY, a citizen of the United States, and residing at Port Chester, in the county of lVestchester and State oiLNew York, have invented a new and. Improved Nut-Tapping Machine; of which the following specification is a full .disclosure. v

This invention proposes various improveby the substitution of one tap. for another,

and in which the various operations will take place smoothly and efliciently, and which will be designed to presenta rugged and durable structure capable of withstanding ,long and hard service. I

Another object is to create a nut-tapping organization which will enable the blanks to be tapped in succession Without permitting them to bind onandbreak the tap through a nut-lock action, and which will promote the free travel of the nut-blanks along the shank of the tap by-so avoiding or overcoming the friction of the, guiding elements that a cramping or congesting of the train of nuts will be precluded;

Another object isto devise-a tint-tapping mechanism in which the nut-blanks may be threaded ata high rate of speed without causing an undue heating of the tool or an undue accumulation of the chips by providing means for maintaining the tap in a forced stream of coolantflowing so rapidly as to wash away the chips as quickly as formed and to keep the tool thoroughly cooled.

Another object is to provide a simple and inexpensive structure whereby the nutblanks will be brought automatically into correct registry with the socket of the chuck notwithstanding the high speed of the latter. and without permitting any clogging'up of the apparatus, and avoid the likelihood of fracture by permitting of the use of rugged and substantial elements.

Another object is to render available a safety control instrumentality which may be relied upon to stop the feeding of nut-blanks into the machine in case the tap should be broken or in case it should become congested with nut-blanks or become otherwise disabled, and to so devise this instrumentality. that 1t may be capable of instant action without depending upon overcoming the inertia of rapidly moving parts such as is necessitated by the stopping of the machine itself. Other objects willbe in part obvious from the annexed drawings and in part indicated in connection" therewith by the following analysis of this invention.

This invention accordingly consists in the features of construction, combinations of parts, and in the unique relations of the:

members and in the relative proportioning and disposition thereof; all as more completely outlined herein.

To enable others skilled in the art so fully to comprehend the underlying features thereof that they may embody the same by the numerous modifications in structure and relation contemplated by this invention, drawings depicting a preferred form have been annexed as a part of this disclosure, and in such drawings, like characters of reference,

denote corresponding parts throughout all the views of which Figure 1 is a side elevation of the assembled machine showing the general arrange ment thereof. Fig. 2 is a detail of the floating tap employed in this machine. Fig. 3 is a horizontal section through the tooling portion of the machine showing certain details of the blank-feeding plunger,'the chuck for receiving and rotating the nut-blanks rela tive to the tap, as well as the automatic stop controlling the feed of the blanks. Fig. 4 is an elevation of the machine at the discharging end thereof showing details of the finger mechanism for promoting the travel of the tapped nut-blank .in the discharging direction. Fig. 5 is a section through line til inclined to the axis of the tap proper details of the drivii'ig gearing. Fig. 7 is a transverse section throagh line T? of Figs. 1 and 12 showing details of the automatic stop-mechanism for controlh the feed of the nut-blanks. Fig. 8 is a section through line SS of Fig. 1 showing further details of the automatic stop-mechanism. Fig. 9 is a fragmentary perspective of the automatic stop-mechanism. Fig. 10 is a perspective of one of the elements of this machine. 11 is an end elevation of the chuck for receiving and rotating the nut-blanks with relation to the tap. Fig. 12 is a plan showingthe machine completely assembled and illustrating various details thereof.

By way of a more general analysis, it may be observed that this invention contemplates the use of a tap preferably of the floating type, as indicated by A, and which is supported solely through the agency of the nutblanks themselves. This tap A has an offset shape designed to enable it to resist displacement in all directions, and it comprises a tooling portion 1 constituting the tap proper having conventional. relieved cutting threads which are adapted to enter the hole of a nutblank to cut internal threads there in in the usual manner. The tap portion is connected with a reduced shank portion 2 ,which, at a suitable point, forms an elbow 3 of a suliiciently great radius to permit of easy passage of a train of nut-blanks. The shank of the tap in this instance continues in the form of portion 4:; the axis of which is 1: preferably at right angles thereto. Tn operation, the tap and its above described offset shank carry a train of blanks somewhat as shown. In the preferred form of this invention, the direction of travel of these blanks is indicated by arrow 5 of Fig. 2.

The means for starting a nutblank on the tap comprises a member B (see 2 and 3) in the nature of a plungerwhich is adapted to abut endwise against a blank to shift it laterally so as to telescope the blank over the end of the tap and enable it to be seized by the threads of the tap so that thereafter the tap may assume control of the blank and draw it progressively over all of the threads of the tap and through the socket of the chuck, as will be understood. At the moment that this plunger B urges the nut-blank against the end of the tap, a force is exerted which moves or tends to translate the tap in the direction of its axis, and, unless it is properly resisted,

"such tap would be forced into an inoperative This displacement is prevented from taking place to any consequential extent by means of an abutment surface 6 which is preferably provided by a positioning member or guide C. This abutment surface 6 extends parallel with the axis of the elf-set extension 4 of the tap on the side position.

in an axial direction thread and greatly impedes the The means for producing relativc rotation between nut-blanks and the tap will comprise a member such as E which is in the nature of a. chuck in that it has a. nutreceiving socket 7 conligurated so that the blanks may travel therethrough without, however, being permitted .to rotate relatively to the chuck or blank holder That is to say, the blanks may translate but not rotate relatively to the holder or chuck; although a relative rotary motion will simultaneously exist between the tap and both the holder and its blanks. This creates a relative rotation between the blank and the tap; accompanied by a sliding shift of the. blanks along the walls of the socket of the blank-holder. lln undertaking to render more practical this general type of machine, I have observed that the effect of this is to create considerable. friction between the blanks and the walls of the socket and this friction must be overcome by the pull of the tap itself. To other words. the plunger. at the instant of engaging a blank with the threads of the tap. forces the tap in a direction to move this extension *1- toward the bearing-surface (3, until resisted by the physical impact of the nut-blanks on the offset portion with said surface 6; whereas, the instant the tap assumes control of the blank, it tends to pull the blank through this holder or chuck and this tends to shift the tap in an opposite direction so as to move the extension 4 away from the surface 6. The extent of this opposite movement is, however. limited by impact of the nutblanks with a complementary bearing-sin face 8 which extends in parallelism with the surface 6 but which is located on the opposite side of the extension 4. So long as the tap is drawing a nut-blank through the bore of the holder E, and while no opposing pressures are-being exerted by the plunger B, the threaded nut-blanks on the extension 4 will be-drawn tightly against the bearing surface 8. l have perceived that this gives rise to a very considerable friction which has heretofore been overcome only by a. crowding of the tram of nut-blanks D forcibly along the surface 8. This, however, tends to crampthe blanks being threaded and operates to produce an imperfect speed and efficiency of the organization. This difficulty among others has now been overcome by the improvements proposed by this invention which include a device constructed and combined'to cause the train of nuts on the off-set portion of the tap to be fed by of contact.

a) force supplementing or independent of that derived from the threading action of the tap and preferably so applied as to become effective either at a definite time in the cycle of operations or whenever the friction at the surface 8'is reduced or relieved. Thus, this invention contemplates an element such as the finger indicated by I which is preferably impositively actuated,

ger F; but, should the friction at 8 be eXcessive, then will the shifting of the blanks be momentarily suspended until the plunger B comes into action to urgea nut-blank onto the end of the tap. This tends to shift the tap in opposition to its drawing-in action and creates a relief of the friction at the point 8 by. momentarily shifting the off-set portion 4 toward the surface (3 and, during this momentary relief, the finger F will be able .toapushthe section of blanks through the guide Calong the oil-set shank. In the normal operation of the machine. this work wi-lilslbe done'qnore or less irregularly depending, of course, upon the.var.ia .tions in the pull on the tap 1 as it threads the successive nuts; butat no time will any congestion be permitted and the various blanks will all be free to leave the threads of the tap in finished form without being opposed by a more or less severe counter-pressure of the already finished blanks. One of the difficulties which has heretofore rendered im practicable a machine of this type has thus been overcome.

Another difiiculty has been that the off-set floating tap has tended to become cramped in its support by a lateral displacement ad'- jacent its elbow. I have ascertained that there is a considerable tendency of the L shaped tap to swerve askew at a point ad jacent the elbow and I have found that by providing an anti-friction bearing. such as the anti-friction roller G, so as to support the train of blanks on the tap adjacent the elbow, that the smooth working of the op-' eration will be materially enhanced,

The torque of the tap, created by the relative rotation between the nut-blanks and the threads of the tap, is received by the bearing surface 9 (see Fig. 1) which extends parallel-with the bearing surfaces 6 and Sand, like the latter, is arranged in off-set relation with the axis of the tap proper to produce the necessary moment-arm; The turning of the nut-blanks with relation to the threads 66 "of the tap results from the relative movement between the nut-chuck E and the member C which as a single unit preferably carries the surfaces 6, 8 and 9 and in this instance, the member C is stationary with the frame of the machine and the nut-holder E is bodily rotated.

Inorder to'carry out the cycle of operations demanded for the above-mentioned major elements, various specific constri1c tions may be resorted to and by way of illustration there has been shown herein a very simple andessentially practicable constructionwhich'may now be described.

The nut-chuokE is shown insection by Fig. 3 and comprises a hub portion 10, which, in this'instance, is journaled in a I portion 11 of the main frame and, is retained in place as by means of a ring 12.which fits over the flange 13. .This chuck has a.

socket 7 adapted to receive thenut-blanks and to rotate the same by engaging the polygonal sides of said-blanks. To that end, the socket 7 provideswalls in the nature of guides for the sides of the nut-blanks and to enable a copious flow of coolant to pass freely around the blanks so as to'wash away the chips made by the tap. This socket preferably provides. canals or channels as indicated by 14 on;Fig. 11. In normal use,,this chuck revolves rapidly, and inasmuch as the blanks are. not revolving when feeding toward it it is essential to provide some means forbringing'theblanks into angular regis- Y In practiceit is found that this arrangement quite efficiently performs, its office.

The chuck may be revolved or driven/in any suitable manner, as by means of. the-ultimately driven gear 16 which is driven in turn by a pinion 17 mounted on the main shaft 18 which is journaled in'pillow blocks 19 and 20 mounted on the main frame of the machine. and which shaft. carries a loose pulley 21 and a fast pulley 22 which may be driven from a suitable source of power by means of a belt 23, as will be understood. In this way the nut-chuck is maintained in a continuous state of rotation. I

The nut-blanks are fed intermittently into the'soeket of the nut-chuck by means of a reciprocating membersB, here instanced as atube, secured in a socket in the end of the actuator 24 (see Fig. 8) and removably held in place by means of;a set-screw 25 v is reciprocated impositively during this forward stroke and positively during its return stroke. That is to say, the forward stroke is executed by means. of the yoked end 27 (see Fig. 8) of the arm 28 extending upward y from a rocker 29 which is pivoted at 30 to the frame. and isin turn actuated by a link 32 pivoted to its lower arm 31. The other end of this link 82 is pivoted to the upper arm 33 (see Fig. '6) of a bell crank lever 34: which is constantly urged clockwise by meansof a weight 35 attached there to through therod 36. lhe advantage of utilizing an impositive force for efiecting the forward stroke of the actuator lies in the fact that parts will not be broken should they meet with an obstruction due'to the clogging" or congesting of the nut-blanks on the tap or in the chuck.

The withdrawal or return stroke ofthe actuator may be eti'ected positively as by means of roller 37 (see Fig. 3) which is mounted atone side of the depending arm 31 and is periodically moved to the left by impacting with the peak 38 of the cam 39 which is secured to a power-shaft 40. This power-shaft extends alongside of the machine and is journaled thereto by means of the pillow blocks 41 and 452 and itcarries a large driven gear 4:3 that isdriven by a pinion i l secured to a large gear 45, and which is in the first instance driven by a pinion l6 -secured to the main power-.

. overlying hopper.

shaft18.

lhe nut-blanks are brought within the sphere of operations of the intermittent plunger by means of a chute 47 (see Fig. 1)

'which is positioned by means of bracket 48 and receives. its supply of blanks from an This chute preferably has a depending lug 4Q pivoted at 50 to the frame so that it maybe moved to one side by releasing the set-screw 51 see Fig. 1)

and thus permitaccess to be had to the parts.

The automatic 821-077 fertile nut-fced.-ln

this embodiment, the nut-blanks descend in the form of a train through an appropriate chute 47 in such a. manner that the lowest blank will drop into the path oi the reciprocating plunger. B which shifts it laterally intothe blank-chuck and onto the tap. Now, in case the tap should become broken or disabled the nut-blanks would accumulate and congest Within the chuck under the actions of the reciprocating plunger and serious damage would be' "c lone to the machine. This is prevented automatically, however, by mechanism which discontinues the supplying of" the blanks in the event'of an abnormal action of the mechanism. The construc tion preferred for this purpose may now be described.

Referring to Figs. 1 and 7. the powershaft 40 is provided with a cam having a pcak'53 located at an appropriate point in the cycle of operations of the machine. ll.

lever Bel is pivoted to the frame of the machine at a point indicated by 5.) so that it may be enabled to be rocked in a given plane, which in this instance is vertical. This lever extends toward the blank-chute and terminates in a finger 56 adapted when the lever is rocked to swing into the path ot the blanks and obstruct the descent thereof. The otheinrud ot' the lever terminates out of the path of the cam 52 and carries a pawl 57 which is pivoted to it at a point 58 so that such pawl swings transversely to the said the resistance of the. spring 0 by a means about to be mentioned. the finger of the lever will be shifted into its obstructing position against the resistance of spring 61 at each cycle of operations of the machine. The pawl 57 is. however, so constructed and arranged in relation to a part moving in unison with the plunger that it will be thrownout of the path of the cam whenever the plunger reaches a station near the end of its forward. stroke. That is to say, a finger (33 constitutes a contact element which advances in synchronism with the advance of the plunger and which, at a predetermined station in such advance. impacts with a foot (32 forming a partof the pawl 57 so as to swing the pawl clockwise against the resistance of the spring (30 and thus bring its contact end out of the path of the cam. ln these circumstances. the cam 52 will be ineiiective to actuate the lever 54: and the spring (31 will maintain the finger 56 out of the path of descent of the nut-blanks; with the result that the nut-blanks are free to gravitate into the path of the plunger during the successive strokes thereof. An automatic stop action takes place. however. whenever the pl linger fails to complete its full forward stroke for the reason that the finder .63 fails. in that event, to bring the pawl out of the path of the camfwith the result-that, at a definite station in the cycle of operations, the .cam throws the obstructing finger into the path of travel of the blanks against the resistance of spring 61 and prevents further feed'of the blanks.

By means of the elements above described, it will be understood that the blanks will be fed at appropriate intervals into the tool ing action ofthe tap so that they will be properly threaded thereby and discharged at spaced intervals onto the shank of the tap. lVhile the tapping of each blank has a continuous operation, it is, nevertheless, to be noted that the bringing of the successive blanks into the sphere of action is executed intermittently so as to leave appropriate intervals or spaces between the successive blanks while on the tap, and, consequently, any .possibility of anut-lock effect is avoided. This structure is, therefore, from one aspect, characterized by the fact that it intermittently, as distinguished from continuously, feeds non-rotating blanks into a rotating blank chuck and then urges the rotating blanks onto a stationary tap, and

. then permits the nut-blanks to draw themselves through the chuck by their forced rotation with relation to the tap. The tooling action of the tap engenders considerable heat which tends to impair the hardness of the metal, and it also forms chips which tend to obstruct the-passage of the blanks and to clog the tap. .This invention, however, proposes means for eflectively overcoming this difiiculty.

The chip remover and tap c00Zer.-The plunger B has a central passage way 64.

i which registers with the bore 65 of the actuator 24:, and by means of a nipple 66 this actuator is in turn connected with a tube 67 ,which receives a forced flow of 'a-suitable coolant, such as water or the like, delivered through the flexible tube 68 by means of a pump 69 driven continuously as by means of a belt 70 deriving motion from a This pump ordinarily employed for the mere lubrication of the cutting threads of a tap. That is to say, the flow of coolant is so copious that the tap is not only kept cool, notwithstanding its high speed and continuous action,

but'the chips are all forcibly washed awayas rapidly as formed; being flooded through the socket of the chuck and washed down the incline chute 71 where they are received in a settlingtank and the liquid coolant is drained through suitable strainers and re turned to the action of the pump 69 so that it is used continuously. This action reduces the liability of stoppage to a minimum, and in combination with the automat1c means 7 for terminating the feed of the blanks in case of any abnormal action a very reliable 'maximum to the other.

organization results. The means for overcoming the tendency of the train of nut blanks to congest on the shank of the tap ,the' point of leaving the threads of the tap; -As has been explained, considerable friction is created where the blanks pass through theguide C and during each cycle of operation, this friction decreases in intensity from one maximum to an inappreciable or negative amount, and then increases in intensity to another maximum. The one maximum is determined by the pressure of the plunger when starting'a nut-blank onto the tap, and the other maximum is determined bythe force required to pull the nut-blanks through the socket of the nut-holder during the thread-cutting period. The automatic stop device proposed in this connection exerts a force on the nut-blanks tending to urge them in a discharging direction duringthe period that the-friction is being varied from the one This friction will undergo quite irregular fluctuations during the normal action of the machine, and at times this device'will be effective to urge the blanks in a discharging direction against the friction somewhat sooner in the cycle of operations than at other times. Thus, it may be inadequate to discharge the blanks always at the same instant in the oycle,but in any event, itwill come into play as soon as the friction is sufficiently relieved by the action of the plunger. The specific construction preferred by this invention may now be detailed.

A carriage 72 is arranged to reciprocate at one side of the L-shaped tap, as by means of the guides'73 provided by an off-set portion of the frame of the machine. This reciprocating carriage has a finger F pivoted to it at 71 about an axis extending trans versely to the shank of the tap and this lfinger projects toward the tap and terminates at a point adjacent the elbow thereof so that,

when it swings inwardly, itmay engage one of the blanks of the train and be madeefiective to push the same in a discharging direction under an appropriate impetus of the tact with the blanks by means of a suitable spring 75. The forward stroke of this finger and the carriage 72 is preferably in the nature of an impositive action and is produced as by means of a lever 7 6 having a toe 7 7 bearing against the carriage; which lever is urged anti-clockwise by means of a spring or Weight 78. A handle 7 9 extending -from the leverTO conveniently enables the pressure of the weight to be relieved for purposes of mspectlon or adjustment. The re turn stroke of the finger is produced posi-' tively by means of a lever 80 pivoted at 81 to the frame of the machine and terminating in a shoe or roller 82 located in the path of a cam 83 mounted on the power-shaft 40 so that at each revolution of the latter the lever 80 will be Withdrawn out of contact vviththe pin 84 to permit the carriage to advance under the control of the Weight and thereby create the desired impositive propulsion of the train of blanks on the tap. The-instant the friction is sufficiently rereduced, the weight 78 will be enabled to advance the blanks, and then the cam 83 Will again withdraw the finger F to its original position. The finished nut-blanks will successively drop off of the end of the off-set portion 4 of the ,tap and will be received by the chute 85. c

The means presenting stale cramping of the t'ap.This comprises an anti-friction support for the blanks on the shank of the tap adjacent the elbow thereof and this support is here instanced as a roller G having a groove 86 of sufficient size to receive and guide a trainof blanks in alinement Withthe axis of the tap proper. This roller is suitably journaled on the frame of the machine as by means of an extension 87 bolted thereto. In conjunction with the support G a secondary support, shown in perspective by Fig. 10 and indicated by H, may be arranged adjacent the delivery end of the socket of the chuckso as to support the tag through the train of blanks by means of a semi-circular shelf 88. v

The guide member C, which provides the bearing surfaces 6, 8 and 9, preferably has a tubular form and is removably supported by a bracket 89 secured to the frame of the machine. A pin 90 will. suffice to hold the guide C in position during the operation of the machine, and a slot 91 will enable the guide to be removed for purposes of'replacement or repair by bringing the pin 90in alinementwith said slot.

Referring again to Fig. 11, it is to be noted that the aperture 7 of the nut-chuck has a peculiar conformation in that it provides two parallel flats 91 and 92 which are spaced apart only sufiiciently to give a little clearance for the adjacent faces of the nutblanks. Then flats extend for the full length of the bore of the nut-chuck and have been formed to reduce the friction to such a degree as to render unnecessary the feeding finger in certain cases. To direct the nut blank along a central line, whereby it may properly engage the tap, side walls 93 and 9& may be extended for a short distance in closeproximity with the blanks and, to provide ample space for the discharge of the meme? chips, may thereafter flare away funnel-like toward the discharge side of the nut-chuck as indicated by the dotted lines 95 and 96.

Having thus revealed this invention, I claim as new and desire to secure the following combinations of elements, or equivalents thereof, by Letters Patent of the United States i 1. A nut-tapping machine of the nature disclosed combining a tap; a nut-blank holder; means for rotating one of said parts relatively to the other; a guide for conveying a train of threaded blanks adapted to position said tap through the agency of said blanks; means for intermittently feeding blanks to said holder; and automatic means for engaging the nut blanks after being threaded by said tap to urgethem through said guide. 2. A nut-tapping machine of the nature disclosed combining a tap; a nut-blank holder; means for rotating one of said parts relatively to the other; a nut-blank chute for feeding a train o f.nuts to the entrance of said holder; an impositively actuated member adapted impositively to urge the end nut-blank into said holder and into engagement with said tap; and means restraining the progression of the blanks in said chute Whenever said member is prevented from making a full forward stroke.

3. A nut-tapping machine of the nature disclosed combining a tap terminating in the other; and an anti-friction roller-bearing adapted to contact adjacent said holder with the train of nut-blanks guided by said tap anti-frictionally to cooperate with said blanks to maintain the position of said tap, said roller-bearing havin its axis extending parallel with the said 0 set'portion of said tap.

4. A nut-tapping machine of the nature disclosed combining a tap; a nut -b1ank holder provided with an aperture having two oppositely located parallel bearing surfaces 91 and 92 adapted to contact the opposite faces of a polygonal nut-blank to prevent it from rotating relatively to the holder Without restraining an axial trans lation thereof, the connecting walls of said aperture being relieved to provide clearance for the nut-blank; means for rotating one ,of said parts relatively to the other; and

means for feeding nut-blanks into engage ment With the aperture in said holder.

5. A nut-tapping machine of the nature disclosed combining a tap having an-ofi'set I tion of said tap and adapted through-a train of nut-blanks to maintain the position of said tap; means for rotating one of said guides with relation to the other; and means for intermittently urging said blanks along the ofiset portion past said adjacent guide.

6. A nut-tapping machine of the naturedisclosed combining a tap having an offset shank portion; a nut-blank holder; means for intermittently feeding nut-blanks to said holder; a member cotiperating with the nutblanks located on the offset portion of said tap and adapted to cooperate in positioning the taps; and means assisting to overcome the friction between the nut-blanks and said member to promote the feeding ofsaid blanks.

7. A nut-tapping machine of the nature disclosed combining a tap; a nut-blank holder having .a socket in co-axial relation with the tooling end of said tap; means for producing relative rotation between said tap and said holder; means for feeding blanks into said socket to engagewith the tooling end of said tap; and an intermittently operating finger adapted to impact a train of nut-blanks on the shank of said tap to cooperate in moving the'same.

8. A nut-tapping machine of the nature disclosed combining a tap; a nut chuck; intermittently acting means for'intermittently feeding nut-blanks to said chuck whereby they may be threaded by a relative rotation between said chuck and said tap; a chute for feeding nut-blanks to said means; a normally-stationary part adapted to obstruct the feeding of said blanks in saidchute and mechanism'adapted to'move said part. into obstructing position when said means fails to execute its normal cycle of move-" I means efiective to feed blanks along the offment.

9. A nut-tapping machine ofthe nature disclosed combining a nut-blank holder pro- I vided with a socket having opposite surfaces adapted to guide a blank and having a relieved face; a tap having its tooling end projecting co-aXially into said socket; means for rotating said parts relatively to one another; a tubular plunger adapted to project a nut-blank into the socket of said holder and into engagement with the tap therein; and means for forcing a copious flow of coolant through the bore of said plunger and into said socket to cool the tap and wash away the chips through the clearance space provided by the relieved face of said socket.

10. A nut-tapping machine of the nature disclosed combining an L-shaped tap; a plunger for urging an apertured nut-blank into engagement with the threaded end' of said tap; a member adapted through the agency of nut-blanks on the off-set portion of said tap to resist displacement of said tap under the thrusts of said plunger; means tween said tap and the nut-blanks on the threaded portion thereof, said means tending to displace said tap in the direction of retreat of said plunger until resisted by said member; and an hnpositive device adapted to urge the train of nut-blanks along the off-set portion of said tap at the instant said plunger starts to retreat.

11; A nut-tapping machine of the nature disclosed combining a tap having an off-set shank portion; a nut-blank holder having a .socket' for containing a nut-blank and for supporting the threaded end of said tap through the agency of said nut-blank; a member positioned adjacent the off-set portion of the shank of said tap providing a bearing surface adapted to contact with a nut-blank on said portion to position the other end of said tap; means for producing a relative rotary movement between said member and said holder about the axis of the latter; and an anti-friction device located between said member and said holder and bearing against a nut-blank on the shank of said tap adjacent the elbow thereof.

12. A nut-tapping machine of the nature disclosed combining a tap having a threaded end and an off-set shank portion; a plunger adapted to urge a blank against the end of said tap to engage the threads thereof; means for causing said blank to rotate relat'ively to said tap to travel along the threads thereof; means presenting a first and second bearing surface adapted to co-act with a blank on the off-set portion of said shank to relieve the advance shift of said tap underthe action of said plunger as well asfthe shift of said tap under the pull of blanks and the threaded portion of said tap;

and means intermittently engaging threaded blanks to feed the same along the shank away from the threaded portion of the tap.

14. A nuttapping machine of the nature disclosed combining a chuck having a socket whereby nut-blanks may be passed through said .chuck and. restrained from rotating relatively to said chuck; a tap arranged co-- Y axially with said socket adapted intermittently 'to thread said blanks; a chute for feeding blanks into co-axial registry with said socket; an impositively actuated plunger adapted to urge a registry blank into said socket and into engagement with said tap; a finger normally aside from the path of the blanks in said chute; and means for automatically interposing said finger in said path whenever said plunger fails to execute its full forward stroke.

15, A nut-tapping machine of the nature disclosed combining a tap having an off-set shank portion; a support operating through blanks entrained on said tap for positioning the off-set portion thereof; a holder for blanks located at the threaded portion on disclosed combining a rotatable memberhaving a nut-receiving socket; a non-rotatable tap having its threaded portion extending into the exit end of said socket; a chute enabling nut-blanks to be placed at the entrance of said socket; means for intermit- I tently displacing nut-blanks into said socket whereby theymay be rotated by said me1nbeij and caused to be fed upon and threaded by said tap; a part normally out of the path of the blanks in said chute; a power-driven element, and interponent mechanism adapted 'wlien actuated by power derived from said element to shift said part into the path of said blanks, said means controllingthe operative connection between said mechanism and said element.

17 A nut-tapping machine of the nature disclosed combining a member providing an elongated polygonal socket; a plurality of elements having rounded portions and mounted on said member at the entrance of said socket andadapted to receive and bring a polygonal nut-blank into angular registry with the guides of said socket; means for feeding nut-blanks past said elements and into said socket whereby they may be prevented from rotating relatively to said member;a tap adapted to be engaged by said blanks; and means for producing a relative rotation between said memberand said tap to thread said blanks;

18. A nut-tapping machine of the nature means for tapping said blanks while being rotated by said member.

19. A nut-tapping machine of the nature disclosed combining a rotatable member having an elongated socket adapted to re ceive and positively rotate a polygonal nutbla'nk; aplurality of hardened balls mounted symmetrically on said member concentric with its axis and adapted to receive and bring a succession of nut-blanks into registry with said socket; and'means for tapping said blanks while being rotated by said member.

20. A nut-tapping machine of the nature disclosed combining a rotary chuck having elongated socket adapted to receive'and positively rotate hexagonal nut-blanks; six rounded elements symmetrically disposed at the entrance to said socket; a tap extending into said socket in concentric relation therewith; and a reciprocating member termi: nating in a cylindrical end adapted to impact and urge a blank into said socket and into engagement with said tap whereby it maybe rotated by said chuck and caused to be drawn through said socket by the screwlike action of said tap.

In witness whereof, I hereunto subscribe my name, as attested by the two subscribing witnesses. I

, WILLIAM D. RIGNEY.

Witnesses:

WALTER E. Lo'rz, HOWARD E. MAnsHALL. 

